“…PSO is quite recent in the framework of geophysical data inversion (Shaw and Srivastava, 2007;Yuan et al, 2009) and is not yet as widely as the other global optimization methods mentioned previously. However, it was successfully applied to surface-wave analysis (Song et al, 2012;Wilken and Rabbel, 2012), traveltime tomography (Tronicke et al, 2012;Luu et al, 2016), seismic refraction (Poormirzaee et al, 2014), seismic wave impedance inversion in igneous rock (Yang et al, 2017) and multifrequency GPR inversion (Salucci et al, 2017). Furthermore, Song et al (2012) have shown, in a comparative analysis, that PSO outperforms genetic algorithm and Monte-Carlo methods in terms of reliability and computational efforts.…”